winch or arm servo?

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Dave Pickett
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winch or arm servo?

Post by Dave Pickett » 13 Nov 2010, 15:26

can anyone advise on the merits of each on an IOM? am I right in assuming that the arm servo is easier to set up? I am looking for a no hassle reliable means of sheeting, all suggestions welcome!

Neil Armstrong
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Re: winch or arm servo?

Post by Neil Armstrong » 13 Nov 2010, 20:38

Hi David,

go for a Smartwinch (RMG) from Australia, i would recommend the 280 ES but if you go on the website you may choose something else.
You will find that although the Smartwinch is slightly more expensive than other winches on the market it is by far the most reliable with great aftersales care thrown in.
I would say that over 90% of competitors in World championships use this winch and lets face it, these boys know there stuff.
You will find them extremely easy to set up although i think most people now set up the travel on the winch using the TX which is also very easy to do.

Aaron Plazier
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Re: winch or arm servo?

Post by Aaron Plazier » 01 Dec 2010, 01:54

Dave I am no expert :P but I ordered a Hitec HS-785HB Sail winch servo for my 1st boat.
AU $37.38 free post off ebay...
No way in same league as the RMG ones but for me it's fine to do my apprenticeship with. :lol:

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Olivier Cohen
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Re: winch or arm servo?

Post by Olivier Cohen » 01 Dec 2010, 12:08

785 HB is very very slow and not suitable for competition.

I use an Hitec 5755 servo with Bantock wheel on it. Very fast and cheap(around 60€), but needs a lot of care in installation to get enough power. There is a new powerful Servo by Hitec 7980TH more expensive but lot of power.

RMG is the easy way.

Dave Pickett
Posts: 107
Joined: 18 Oct 2010, 19:33
Sail number: GBR3845
Club: Eastbourne
Design: TS2 and Shiraz

Re: winch or arm servo?

Post by Dave Pickett » 01 Dec 2010, 20:36

Thanks guys, I have been looking at winches for some time and so far given price and performance, this is the front runner:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 2873wt_924

and at less than £20..........
HS-785HB
Thanks, although I really like the simplicity of an arm servo, I will give this some serious thought, maybe running on 7.4volt lipo it will be quick enough.....

Seems the rotary winches are favorites, anyone care to post a picture of their running rigging set up and particularly how the cord is tensioned......

Bruce Andersen
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Re: winch or arm servo?

Post by Bruce Andersen » 01 Dec 2010, 22:54

If you are racing, initial cost is not the only consideration:

Is an inexpensive servo worth the hassle of traveling to a regatta then not sailing due to servo failure?
Is an arm winch setup worth the hassle of traveling to a regatta then not sailing due to the arm getting tangled up or the servo burning out?

At any major regatta, count the number of boats disabled due to either failure of a cheap servo or something fouled up in the arm winch sheeting set up.

Then count the number of boats disabled because the RMG winch failed.

If memory serves correctly I think I've seen 1 (one) RMG fail (this does not count the one that caught on fire & burned up at the Blow Out a few years ago - that was a combination of battery + a lot of water = fire), in contradistinction to regular problems with arms etc.

My point is: sure an RMG costs a lot more, but amortized over the 10-20 years of regatta use it should last, they are the most cost-effective option. As someone posted earlier, an RMG winch is probably going to be the most dependable part of your entire program.

I neither own stock in, or am being paid by RMG.
Bruce Andersen - USA 16

Aaron Plazier
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Re: winch or arm servo?

Post by Aaron Plazier » 02 Dec 2010, 05:39

I know you are after winch servo options but small diversion for my own interest...
Rudder servos?
I bought a digital metal geared, coreless motor, double b/bearings servo about 39g..
4.8v torque 8kg/cm
6v torque 11kg/cm

I am running off memory on specs but will that be sufficient?

Patrick Parisienne
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Re: winch or arm servo?

Post by Patrick Parisienne » 08 Dec 2010, 23:45

More than enough power! Anything over 4kg is strong enough. I too like digital servos for their self centering resolution, and speed. I use a Hitec 5485 HB for all the classes I sail.
One thing you may find if running an RMG winch alongside that servo is that the winch may jitter after a big rudder input, due to current draw. The RMG website has info on this. If this occurs, just change rudder servo to a less powerful one, about 7kg/m or less will be fine.

Cheers,

Pat

Aaron Plazier
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Re: winch or arm servo?

Post by Aaron Plazier » 09 Dec 2010, 11:08

thanks for that!

Ralph Knowles
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Re: winch or arm servo?

Post by Ralph Knowles » 18 Dec 2010, 14:16

I have been more than happy with the Hytec 1/4 scale servos like the 5735 and 5745 set up with the CF lever arm as used by Trevor Binks at the Van. Can. Worlds, which he won. My 5735 has been working perfectly since new seven years ago and I have also fitted out another three hulls similarly. Recently, due to problems with the weight budget in a home design and also an Arion, both built in cedar, I have been experimented with the Eurgle #22 drum winch. I use this unit with a 1:2 ratio shieve system to speed up the sheeting. Its not quite as fast as a 1/4 scale lever arm which is the fastest, nor an RMG, but it is definitely value for money at £19.50 plus postage directly from the far east.

Ralph
Bring on the Breeze!

Ralph

Dave Pickett
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Sail number: GBR3845
Club: Eastbourne
Design: TS2 and Shiraz

Re: winch or arm servo?

Post by Dave Pickett » 18 Dec 2010, 19:39

Thanks Ralph, I have two of the Eurgle winches (one as a spare) which I am going to start off with and see how it goes. As a beginner I have loads to learn before I worry too much about the speed of sheeting!

Gyula
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Re: winch or arm servo?

Post by Gyula » 09 Jan 2011, 13:58

Gyula Ferencz

Dave Pickett
Posts: 107
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Sail number: GBR3845
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Design: TS2 and Shiraz

Re: winch or arm servo?

Post by Dave Pickett » 11 Jan 2011, 19:05

Useful links, thank you, there's very little actual info about these winches so this helps.

I have two (one as spare) as yet unused as my IOM is in the build phase! One didnt work properly on arrival it merely flicked back and forth rapidly. The ebay supplier was excellent and immediately prepared to replace the unit, but I fiddled with it and turned the drum manually a few times and it now works perfectly! Assume it was dirt or grease on the track of the pot?

Anyway I have a 1200 mah battery so will have to see how long it lasts, as and when I get mine on the water I will report further.....................

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